Along with the technology development and wide application of the optical transport network, the system architecture of the network has an every increasing demand that the optical transport network shall be intelligentized and interconnectable, and the implementation of the entire functional demand of the automatically switched optical network (ASON) in a dense wavelength division multiplexing (DWDM) network becomes a very important practical demand. The automatic discovery serves as a basic function of the ASON function implementation; the automatic neighbor discovery function of control plane may be implemented by using the regeneration section trace tracing byte J0 and the data channel communication byte DCC as the transport mechanism in a synchronous digital hierarchy (SDH) network; there is no fixed transport mechanism for implementing the automatic neighbor discovery function of control plane in a DWDM equipment, which lacks the flexibility in the network intelligence through the mode of manual assignment. A wavelength division equipment transmits dense wavelength division multiplexing signals; various wavelength channels are independent from each other; service signals transmitted by various wavelength channels have no termination function between various nodes; it is not a feasible method to implement the automatic discovery function through the overhead in the frame structure of a service signal transmitted via a certain wavelength channel. At present, a fixed mechanism for implementing the automatic discovery function has not yet been provided in an automatically switched optical network composed of DWDM equipments.